package util;

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class DBUtils {
    private static volatile MysqlDataSource mysqlDataSource;
//    private static volatile Connection connection;

    private static MysqlDataSource getMysqlDataSource() {
        if (mysqlDataSource == null) {
            synchronized (DBUtils.class) {
                if (mysqlDataSource == null) {
                    mysqlDataSource = new MysqlDataSource();
//                    mysqlDataSource.setURL("jdbc:mysql://127.0.0.1:3306/myblog2022?characterEncoding=utf8&useSSL=true");
                    mysqlDataSource.setURL("jdbc:mysql://82.157.146.10:3306/myblog2022?characterEncoding=utf8&useSSL=false");
                    mysqlDataSource.setUser("root");
                    mysqlDataSource.setPassword("12345678");
                }
            }
        }
        return mysqlDataSource;
    }

    /**
     * 两种模式（单例模式的 Connection / 多例模式 Connection【此方法实现】）
     *
     * @return
     */
    public static Connection getConnection() throws SQLException {
        Connection connection = getMysqlDataSource().getConnection();
        return connection;
    }

    /**
     * 关闭资源
     *
     * @param resultSet
     * @param statement
     * @param connection
     * @throws SQLException
     */
    public static void close(ResultSet resultSet, PreparedStatement statement, Connection connection) throws SQLException {
        if (resultSet != null) resultSet.close();
        if (statement != null) statement.close();
        if (connection != null) connection.close();
    }

}
